The present invention relates generally to computer workstations which are connected for information interchange with host or mainframe computer systems; more particularly, the invention relates to a method and apparatus for processing action bars and pull-downs on certain non-programmable workstations by sharing the processing operations amongst a workstation controller, a host processor and a non-programmable workstation. The invention enhances the user interface associated with non-programmable workstations, to be more closely representative of the user interface associated with programmable workstations.
In any typical prior art system utilizing a host processor, workstation controller, and workstations, wherein the workstations are utilized for user interaction and access and the host processor is utilized for running applications programs, the host processor provides certain fundamental information. For example, the host processor may generate a data stream containing information to be displayed on a workstation screen, and information for controlling the presentation and position of the data on the screen. In the case of a programmable workstation (PWS), the host processor data stream is sent directly to the workstation and is processed internally in the workstation, which itself contains sufficient internal memory and program data to directly control the interaction with the display screen and keyboard. In the case of a non-programmable workstation (NWS), the host processor data stream is sent to a workstation controller (WSC), and the WSC provides the internal memory and control for directly controlling the display screen of the NWS. In either case, the host processor-constructed data stream is received by a workstation control interface (hardware and/or software), and the workstation control interface processes the data stream. A workstation controller communicates with attached NWS workstations to determine whether a keystroke should be recognized or whether any of a predetermined number of commands from the workstation controller have been processed.
Although a PWS terminal is of considerably more sophisticated design than an NWS terminal, when it is used in an environment where a host processor executes applications programs and merely utilizes the PWS terminal for NWS-like operator/user interface, the PWS terminal suffers from most of the same limitations as an NWS terminal. For example, each time a display panel is to be changed on the screen of either type of terminal as a result of user interaction, the host processor creates the panel description, and presentation, and constructs a data stream for transmission to the workstation controller.
The inherent superiority of the logical design sophistication of a PWS enables the designer to incorporate certain user interface enhancements into a stand-alone PWS application, which enhancements have heretofore been severely degraded in systems utilizing NWS terminals. One such enhancement, the "action bar," is a widely used PWS enhancement, whereas this enhancement has been degraded in systems having NWS terminals because the internal logical design capability of an NWS terminal is simply too limited to permit the processing operations required. These limitations have forced users of NWS terminals to operate under a different and more limited set of interface rules than users of PWS-based applications. However, since a total system environment may include a host processor connected to a significant plurality of mixed terminals, a system user must be familiar with both sets of operating rules in order to effectively interface with the application program being run, through either a PWS terminal or an NWS terminal.
The necessity that a system user be knowledgeable of different sets of user interface rules seriously compromises the operational effectiveness of the total system. The dilemma arises from the historically competing demands of increased sophistication and uniformity of operation versus the competitive demands of system costs. The marketplace has created a demand for low-cost keyboard/display terminals, which has resulted in the widespread use of NWS terminal devices; system users have created a demand for increasingly sophisticated and "user-friendly" interactions with applications, which has led to the design of the PWS terminal devices. Computer manufacturers, in an effort to satisfy these competing demands, have devised uniform system architecture rules to enable the interconnection and shared usage of both NWS and PWS terminals in the same system. To the greatest extent practicable the user interface rules for these mixed systems have been uniformly devised. For example, International Business Machines (IBM) has defined a "systems application architecture" to layout a common set of rules for system design and interconnection of subsystems. The user interface to the system application architecture is also defined, and reference should be made to an IBM Publication No. SC26-4351- 0, entitled "Common User Access-Panel Design and User Interaction." These common user access (CUA) rules define and describe the techniques and conventions to enable application designers and developers to create various application software that will operate effectively on a wide variety of different IBM computer systems. CUA is one part of the IBM systems application architecture (SAA), which is a complete set of selected software interfaces, conventions, and protocols that serves as a common framework for application development, portability, and use on multiple system types. Among the IBM systems to which these rules apply are the System/370, IBM Personal Computers, and AS/400 System. The CUA rules are uniformly devised except, as here, where hardware limitations prevent such uniformity.
The present invention overcomes apparent hardware limitations in NWS devices to enable, for the first time, the processing of PWS-like "action bars" in display screen constructs for such devices which appears to be identical to PWS devices. An "action bar" is a list of available action choices from which users select one choice, which results in the screen presentation of an associated pull-down menu, in which the user is requested to select options or parameters associated with that action. Reference should be made to the aforementioned IBM publication for a description definition and presentation of action bars and pull-down menus, and for the user interaction with action bars.